Pistons for internal combustion engines



Oct. 1965 J. L. HARRAH 3,212,410

PISTONS FOR INTERNAL COMBUSTION ENGINES Filed Sept. 9, 1963 P I9 21 E ,2|

I INVENTOR United States Patent 3,212,410 PISTONS FOR INTERNAL COMBUSTION ENGINES John L. Han-ah, 43 Center Road, Bedford, Ohio Filed Sept. 9, 1963, Ser. No. 307,429 4 Claims. (Cl. 92--218) This invention relates broadly to improvements in pistons for use in internal combustion engines.

The primary purpose of the present invention is the provision of an improved form of piston construction whereby the piston packing may be removed, repacked and overhauled, and replaced from the top of the motor without disturbing the many other precision finished parts of the engine.

Another object of the invention is to provide a piston to prevent loss of compression pressure due to leakage between the pistons and the cylinder walls and also to retain the motor oil in the crank case.

Another purpose of the invention is the provision of a removable head piston to operate in conjunction with an improved form of piston packing thereby to form a sealing relation against the cylinder walls of the internal combustion engines.

Another purpose of the invention is to provide an inexpensive and simplified removable head section, one that will be facile in operation and also one to hold the piston packing assembly in position around the piston.

Another purpose of the invention is to afford an inexpensive and simplified means of repacking and overhauling the removable head pistons which are especially adapted for use in commercial and industrial trucks, local and long distance trucks and buses, taxi cabs, police cruisers, Diesel, road and farm machines and associated engines. By repacking and overhauling the pistons from the top of the motor it will be easier, cleaner, less expensive to do and it will, only for a relatively short time, tie up much needed equipment.

These and other objects as well as the nature and advantages of the invention will be more readily apparent from the following description taken in connection with the accompanying drawing and in which:

FIGURE 1 is a top plan view of the removable head. FIGURE 2 is a cross sectional view of the same taken on line 22 of FIGURE 1. FIGURE 3 is a fragmentary sectional view of the head taken on line 44 of FIGURE 2. FIGURE 4 is a top plan view of the piston main body with the removable head removed. FIGURE 5 is a sectional view of the piston. FIGURE 6 is a front plan view of an Allen head set screw.

Referring more particularly to the drawings and in FIGURES 1 and 2 a removable piston head 17 is shown. Said head 17 consisting of a substantially thick, flat, annular portion having threaded set screw bores 1818 extending downwardly therethrough. The underneath surface of said head 17 being possessed with L shaped lugs 19-19 extending integrally and downwardly therefrom. The lower portions 1414 of said lugs 1919 extend perpendicular to the head axis and extend in opposite directions.

In FIGURES 4 and 5 it can be seen that the piston consists of a main body 16. The main body 16 consists of a substantially thick, hollow, cylindrical portion having a skirt 20 with a reduced portion 21 extending circumferentially thereon and having wrist pin bosses 22 positioned immediately above said skirt 20.

Said main body 16 being possessed with one open end 23 and one closed end 24.

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The top or closed end 24 of said main body 16 has correlating open apertures 2525 extending from its top peripheral surface downwardly therethrough. Said apertures 2525 being positioned inwardly and away from the outer circumference of said top 24.

Thus to assemble the removable head 17 is placed over the top of the main body 16. Thus the lugs 1919 are lowered downwardly through the said body apertures 2525 and with partially turning said head 17 to the right said lugs 1919 will become securely engaged with the underneath surface 36 of said closed end 24 of said main body 16.

To prevent accidental movement of said head 17 upon said body 16 the set screws 26 as shown in FIGURE 6 are inserted and screwed into the said threaded bores 18-18 in said head 17.

Said set screws 26 are known as dog point set screws. The threads become engaged with thethreads in the piston head 17 and the rounded points (unthreaded) enter into the unthreaded bores in the closed end 24 of the piston top.

With the use of such a piston construction and employing the use of an improved form of piston packing it would allow the packing to be removed and replaced from the top of the motor. It would also control the blow-by and compression pressure primarily because of a much closer fit of the heat treated detachable head in the cylinders. It would also retain the motor oil in the crank case.

For these and other reasons it is to be understood that the illustrative construction I have shown may be modified in various respects Without departing from the spirit and scope of my invention and it will be understood that it is my intention to include all such modifications in the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a removable head piston of the class described, comprising a main body and a removable head, said main body being of substantially thick, hollow, cylindrical construction having a skirt with a somewhat reduced area extending immediately above said skirt for the purpose of carrying an improved form of piston packing, said skirt having wrist pin bosses extending axially therethrough, said main body being open at one axial end and closed at the opposite axial end, said closed end being possessed with correlating apertures extending from its top face downwardly therethrough; said removable head being of substantially thick, fiat, annular construction with its underneath surface being possessed with integral, correlating L shaped lugs extending downwardly therefrom, the lower part of said lugs extending in opposite directions, said head being adapted to be snugly received upon said main body with said lugs passing downwardly through said body apertures, with slight rotation of said head said lugs become securely engaged with the underneath surface of said body head, means to prevent accidental movement of said head upon said body.

2. In a piston consisting of a main body and a removable head, said main body being of substantially thick, hollow, cylindrical construction having a skirt with a reduced area extending circumferentially above said skirt and having wrist pin bosses positioned immediately above said skirt, said main body being open at one axial end and closed at the opposite axial end, said closed end having apertures extending from its top face downwardly therethrough; said head being of substantially thick, an-

nular construction with its bottom surface being disposed with correlating lugs extending downwardly therefrom, said head being so proportioned to be rotatably received upon said main body with said lugs passing downwardly through said body apertures, with rotation of said head upon said body said head lugs will become engaged with the underneath edges of said body apertures, means to prevent accidental movement of said head upon said body.

3. In combination, a cylindrical piston comprising a substantially thick, hollow main body having a skirt with wrist pin bosses positioned immediately above said skirt, the top peripheral surface of said body being possessed with two open apertures extending from its top face downwardly therethrough, said body having a reduced diametrical surface for the purpose of carrying a piston packing, said piston head being of substantially thick, flat, annular construction with its underneath surface being possessed with two lugs extending downwardly therefrom, said head being adapted to be rotatably received upon said body with said lugs passing downwardly through said open apertures, with partial rotation of said head upon said body, said lugs become securely engaged with said open apertures, said head thereby seals said packing upon said body, means to prevent accidental movement of said head upon said body.

4. In a piston consisting of a substantially thick, cylindrical main body and a removable head; said main body having a skirt with wrist pin bosses positioned immediately above said skirt, said body having a reduced diametrical section for the purpose of receiving a piston packing, said body having one open and one closed axial end, said closed end having a plurality of open holes extending downwardly therethrough, said head having a plurality of L shaped lugs extending downwardly therefrom, said head being adapted to be rotatably received upon said body with said lugs passing through said open holes, said lugs thereby engaging said body top, said head thereby sealing said packing upon said main body, means to prevent accidental movement of said head upon said body.

References Cited'by the Examiner UNITED STATES PATENTS 1,312,879 8/19 Turner 92-221 1,701,355 2/29 Borland 92218 1,723,187 8/29 Lemieux 922l8 2,069,437 2/ 37 Frank 92218 2,361,095 10/44 Hairrah 92218 2,478,179 8/ 49 Brockmeyer 92216 KARL I. ALBRECHT, Primary Examiner. 

1. IN A REMOVABLE HEAD PISTON OF THE CLASS DESCRIBED, COMPRISING A MAIN BODY AND A REMOVABLE HEAD, SAID MAIN BODY BEING OF SUBSTANTIALLY THICK, HOLLOW, CYLINDRICAL CONSTRUCTION HAVING A SKIRT WITH A SOMEWHAT REDUCED AREA EXTENDING IMMEDIATELY ABOVE SAID SKIRT FOR THE PURPOSE OF CARRYING AN IMPROVED FORM OF PISTON PACKING, SAID SKIRT HAVING WRIST PIN BOSSES EXTENDING AXIALLY THERETHROUGH, SAID MAIN BODY BEING OPEN AT ONE AXIAL END AND CLOSED AT THE OPPOSITE AXIAL END, SAID CLOSED END BEING POSSESSED WITH CORRELATING APERTURES EXTENDING FROM ITS TOP FACE DOWNWARDLY THERETHROUGH; SAID REMOVABLE HEAD BEING OF SUBSTANTIALLY THICK, FLAT ANNULAR CONSTRUCTION WITH ITS UNDERNEATH SURFACES BEING POSSESSED WITH INTEGRAL, CORRELATING L-SHAPED LUGS EXTENDING DOWNWARDLY THEREFROM, THE LOWER PART OF SAID LUGS EXTENDING IN OPPOSITE DIRECTIONS, SAID HEAD BEING ADAPTED TO BE SNUGLY RECEIVED UPON SAID MAIN BODY WITH SAID LUGS PASSING DOWNWARDLY THROUGH SAID BODY APERTURES, WITH SLIGHT ROTATION OF SAID HEAD SAID LUGS BECOME SECURELY ENGAGED WITH THE UNDERNEATH SURFACE OF SAID BODY HEAD, MEANS TO PREVENT ACCIDENTAL MOVEMENT OF SAID HEAD UPON SAID BODY. 